1. Field of the Invention
The invention relates to an oscillation system for a watch, having a spiral balance spring, the inner fastening point of which is connected to a balance staff, in particular by means of a collet, the outer fastening point of which is connected to a retaining element, in particular by means of a balance spring stud.
2. Description of the Related Art
An oscillating system for a watch is isochronous if it has the same oscillation period at any amplitude. Amplitude in this case is the oscillation range of the balance. The amplitude varies depending on the state of winding and, among other things, the conditions of friction in the watch. For example, the friction of the balance in flat positions is not the same as in suspended positions. As a result, the watch will usually have a higher amplitude in the flat position than in suspended positions.
One possibility for eliminating the isochronism error involves the use of a regulator. Depending on the distance of the regulator pins, oscillations at small amplitudes can be speeded up or slowed down. This means, however, that the watch without a regulator must run significantly faster at low amplitudes than at high amplitudes. This condition is achievable by the appropriate selection of the fastening points.
The use of a regulator involves expense. Furthermore, additional isochronism errors can be caused by the regulator. In addition, regulator pins can wear and can have a negative influence on the long-term performance of the watch.